1. Field of the Invention
The present invention relates to an information processing system and an information processing method.
2. Description of the Related Art
Recent years, as a technique to measure a distance to an object, a stereo matching process using the triangulation principle with a stereo camera that includes two cameras has been used. The stereo matching process is a process of calculating a distance between a stereo camera and an object included in an image based on a parallax value obtained by matching corresponding regions in a reference image that is captured by one camera and in a comparison image that is captured by the other camera.
However, if a texture is weak in an image in which an object being a subject is captured, when the stereo matching process described above is performed, it is difficult to match corresponding regions appropriately, and it is difficult to derive an accurate parallax value. The texture herein signifies, for example, a figure, a pattern, an arrangement, color, dots, and the like that appear due to respective pixels being dark or light in an image.
Therefore, a technique has been proposed in which a texture is formed by irradiating light having a pattern (hereinafter, pattern light) from a light emitting unit, and the stereo matching process is performed on an image of a subject on which the texture is formed (Japanese Patent Laid-open Publication No. 2012-181142). The pattern of the pattern light herein is a distribution of intensity of light, a distribution of color, or the like to create the texture described above. As described, by performing the stereo matching process on an image on which a texture is formed, the accuracy in deriving a parallax value is improved.
However, in the technique described in the above patent literature, there is a possibility that accuracy in recognizing a subject is affected, for example, when an abnormal condition, such as a state having blocked-out shadows, a saturated state with blown-out highlights, and reflection of light from a light emitting unit, occurs in an image depending on a condition of placement of a subject.
In view of the above problem, there is a need to provide an information processing system and an information processing method in which deterioration of accuracy in recognizing a subject can be suppressed.